Expansion reamer



sept. 29, A1925.

L. YOUNG EXPANSION REAIIER Filed Nov. 22 1921 n t a L5 3f 5%/ f Patented Sept. 29, 1925.

UNITED. STATES :tuinman.1..r YOUNG, or .sroxann WASHINGTQNQ EXPANSION BEAMER.

Application led November 22, 1921.

To all whom t may concern.;

Be it known thatl, LUTHER L. YoUNG, a citizen of the United States, residing at Spokane, in the county of Spokane and State of Washington, lhave invented new and useful Improvements in Expansion Beamers, of which the following is a specication.

This invention `relates to expansion reamers and while adapted for anyclass of work to which a reamer is usually applied, it is particularly designed for use in reaming' axially aligned bores such as` the wrist pin' bearings in pistons.

One of the objects of the invention. is the provision of a tapered spindle on which. are mounted split cylindrical guide and :cutting elements each having an internal taperlit-A ting the taperedspindle, said elementsbeing expanded by vforcingthem toward `the enf larged end of the tapered spindle, the. eX- ternal diameter of said guide and cutting elements being maintained equal throughout.

dle between said guide and cutting elements, andacting asa thrust member to transmitr the force applied to one of said elements by the adjustingineans, to the other of said elements,y in either direction.

Another object of the inventionis to provide a longitudinalgroove in said spindle andkeys for said guide and cuttingelements, tting said groove, by-which said elements are splinably mountedu relative to said spindle.

A further object of the invention; is to provide a split cutting element having projecting spiral cutting teeth by virtue of which said cutting element `will ream a round hole in a bea-ring 4or through an. aperture provided with a longitudinal groove;

Still another object of the invention is the provision of hollow-split guide and cuttingelements, the walls of each being thin nest ladiacenti the split portion thereof and thickest @1e-the side oppesite said isplitporm.

Serial No. 517,05*?.V

tion, said guide and cutting elements being providedwith teeth which are proportion, ately longer as. they approach .the split portion of the walls of said elements so that the surfaces of said teeth lie inthe surface'. of a cylinder "the .aXisof which is coincident= with the axis of rotation of .said spindle.

With the above and other objects in view7 myinvention `consists inthe improved *exe pansion reamer, illustrated in the. accoinl panying drawings, described in thefollow# ing specification, and` particularly claimed,l and in such variations and modifications thereof-aswill be obvious to `those skilled in the artto which my invention relates. 1

In the drawings accompanying and form,- ing a part `of'this specication, and 'wherein the preferred embodiment `of my. yinvention is illustrated Figure lis a side `elevation of my im proved reamer with a portion thereof `shown -in' lsection,the guide and cutting elements being expanded.

Figure 2 is a View showing the cutter and guide elements in contracted position..

Figures 3 and .tare cross sectional views of the cutting and guideI elements `taken re-. spectively along `the lines 3-,3 and 4--4l .of Figure 2. y

Referring in detail to the severaliigures the numeral 1 represents Va spindle havinga wrench-hold 2 adjacent the upper end thereof and having a portionB gradually tapered downwardly toward itslower end.` Mounted on said tapered portion is the guide element 4 and the cutting element `5, each hav'- ing projecting teeth on its exterior surface,

which lie within-'the` surface ofA a, cylinder the aXis of which coincides with the axis Vof rotation of the spindle' 1. The guide and cutting elements` are each formed with frusto-conical bores ofthe. same pitch as; the ta-l pered portion Bof the spindle so'that they4 fit said spindle when placed thereon.| The wall 6 of the guide element 4 is of gradually increasing thickness from-a point 'ong its periphery to a pointldiametrically opposite and of gradually decreasingthickness@ from the latterto the former point. Simi# larly, the wall 7 of the cutting element 'is of gradually increasing thickness vfrom a.. point on its periphery to a pointdiametrically opposite and of gradually decreasing thickness from the, `latter tothe former point. Said ,walls aresplit in their thinnest* in suitable keyways formed on the surface of the spindle 3 and which permit endwise movement of said elements at 4the same time .preventingrotation thereof relative to said spindle. The end surfaces of said guide and cutting elements are preferably beveled as at 20and between Vthe inner end surfaces of said elements is arranged a collar 13 which ris preferably unsplit and loosely surrounds said spindle, said collar acting as a thrust member to transmit longitudinal force, which may be applied at one end of the cut-.

ting element, to the guide element and, vice versa, to transmit force applied to the guide s element to the cutting element.

The spindle l is threaded as at 14 and at the opposite ends of the tapered portion and upon these threaded portions lnuts l16 and 17 are mounted, said nuts having. socket portions 21 and 22, respectively, the ends of which are preferably beveled inwardly to receive and engage the beveled outer ends of the. guide element 1 and the. cutting. element 5, respectively. Shoulders 18 andr 19, respectively, are formed on the interior `of the nuts 16 and 17, respectively,at the point where the threaded portion joins'thesocket portion. The shoulder 19 of the nut 17 mounted on that end of the tapered portion 3 which is of smaller diameter functions asv a limit stop to prevent excessive expansion of the guide and cutting members beyond the maximum capacity for which they were designed.

In operation the guide and cutting elements are expanded by loosening the nut 16, advancing the nut 17 the required amount,

and then tightening backthe nut 16 toi hold' said elements rigid in their new position of adjustment, For contracting said elements the operation is reversed, that is, the nut 17 is backed off, the nut 16 is advanced to kmake the proper adjustment, and the nut 17 is again tightened. It isnot vessential that the tapered portion of the spindle 3 be formed in a single taper, a taper in two stages being permissible, the essential requirement being that the taper or tapers shall have the saine pitch so that the ratio of the diameter of the guide and cutting elements shall not change through the range of expansion of the reamer.

' The guide element t is provided with longitudinal teeth and, while preferable, it is not absolutely essential that a key be provided for this element since it does not act as a cutter and relative rotation between it and the spindle may not be objectionable.

The teeth on the cutting element 5 are spirally arranged so thatit may operate .in a hole having a longitudinal groove in its surface such as the oil groove often found in bearings. The spiral arrangement of teethv also prevents chatter and ensures the making of a smooth surface.

Since the guide and cutting elements have the same diameter at all times, that is to say,

tsince the ratio of their diameters does not change, the device will ream axially aligned holes in perfect alignment, the guide element co-,acting with one hole while the cutting ele- Y ment operates within the other.

Obviously, changes in the details of construction may be made without departing from the spirit of the invention and I do not wish to limit myself to any particular forni,

,or arrangement of parts.

Having described my invention what I claim as new and desire to secure by Letters HPatent, is

1. An expansion reamer comprising a tapered spindle, an expansible guide element and an expansible cutting element, each having a tapered bore corresponding in pitch to that of the tapered spindle and fitted for endwise movement thereon, a thrust collar loosely surrounding said spindle and abutting the adjacent ends of said guide and cutting elements and means for applying force tothe outer end of one of said elements.

2. An expansion reamer comprising a tapered spindle, an expansible guide element and an expansible Acutting element eachv having a tapered bore corresponding'in pitch to that of the tapered spindle, and fitted for endwise movement thereon, a thrust collar loosely surrounding said spindle and abutting the adjacent ends of said guide and cutting elements and means for selectively applying force to the outer end of the guide element or the cutting element for moving said elements endwise in either direction relative lto* said spindle.

3. An expansion reamer, comprising a tapered spindle, a train of contacting elcments mounted on said spindle comprising an expansible guide element, and an expansible cutting element of the same outside bdiameter, each having a tapered bore corresponding in pitch to said tapered spindle, and a collar arranged intermediate the two, means for adjustably moving said train of elements in either direction relative to said tapered spindle and means for securing them in any position of adjustment.

4. An expansible cutting element comprising a cylindrical body provided with a central bore and with radially extending spiral cutting'teeth, the outersurface of said cuti ting teeth lying in the surface of a cylinder the axis of which is coincident With the axis of said central bore, said teeth being of progressively different depth forming a supporting Wall Which is thinner on one side than on the other, said Wall being split spirally at its thinnest portion.

5. An expansible cutting element comprising a cylindrical body provided With a central bore and with radially extending spiral cutting teeth, the outer surface of said cutting teeth lying in the surface of a cyl-- inder the axis oi' which is coincident with the axis of said central bore, said teeth being of progressively different depth forming a supporting Wall which is thinner on one side than on the other, said Wall being split spirally at its thinnest portion and a keyway being provided in its thickest portion.

6. An expansion reamer comprising a tapered spindle having a Wrench hold at its upper end, the tapered portion of said spindle being provided with a longitudinal spline groove, an expansible guide element and an expansible cutting element each hav ing a trusto-conical bore corresponding in pitch to the tapered portion of said spindle and litted thereon, each of said elements being provided With an internally projecting spline registering with said splinel groove, a thrust collar surrounding said spindle intermediate said guide and cutting elements, and a nut threaded on the lower end of said spindle and engaging the outer end of said cutting element.

7. An expansion reamer comprising a spindle having a tapered portion and a Wrench hold at its upper end, said spindle being threaded at both ends adjacent said tapered portion, an eXpansible guide element and an expansible cutting element, both splinably mounted on the tapered portion of said spindle and separated by a thrust collar, a nut threadedly engaging` the upper threaded portion of said spindle and contacting with the outer end of said f element having an internal taper of the same pitch as said tapered portion and mounted thereon, said guide element being split longitudinally and provided With longitudinally arranged radially projecting teeth, a cutting element having a tapered bore corresponding in pitch to the tapered portion of said spindle and mounted thereon, said cutting element being spirally split and having spirally arranged radially projecting teeth, a thrust collar loosely surrounding said tapered spindle contacting With the inner adjacent ends of said guide and cutting elements, a nut engaging the smaller end of said tapered spindle for forcing said cutting and guide elements toward the larger end ci" said spindle and means to limit the longitudinal movement of said nut.

In testimony whereof I have hereunto set my hand.

LUTHER L. YOUNG, 

